【spring cloud】sleuth的简单使用

sleuth是spring cloud框架中，作为消息调用链追踪的组件，起配置相对简单，下面简单介绍一下sleuth的使用。

1，引入依赖

    <dependencies>
        <!--eureka-client-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>

        <!-- spring boot web-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- spring boot actuator-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

        <!-- sleuth -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-sleuth</artifactId>
        </dependency>

        <!-- logback -->
        <dependency>
            <groupId>net.logstash.logback</groupId>
            <artifactId>logstash-logback-encoder</artifactId>
            <version>6.3</version>
        </dependency>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.3</version>
        </dependency>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-core</artifactId>
            <version>1.2.3</version>
        </dependency>


        <!-- zipkin -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-zipkin</artifactId>
        </dependency>
    </dependencies>

2，配置文件

2.1，application.properties

spring.application.name=sleuth-traceA
server.port=62000

eureka.client.serviceUrl.defaultZone=http://localhost:20000/eureka/

logging.file=${spring.application.name}.log

#zipkin的地址
spring.zipkin.base-url=http://localhost:62100

#采样率
spring.sleuth.sampler.probability=1

info.app.name=sleuth-traceA
info.app.description=test

management.security.enabled=false
management.endpoints.web.exposure.include=*
management.endpoint.health.show-details=always

2.2，logback.xml

<?xml version="1.0" encoding="UTF-8"?>
<!--该日志将日志级别不同的log信息保存到不同的文件中 -->
<configuration>
    <include resource="org/springframework/boot/logging/logback/defaults.xml" />

    <springProperty scope="context" name="springAppName"
                    source="spring.application.name" />

    <!-- 日志输出位置 -->
    <property name="LOG_FILE" value="${BUILD_FOLDER:-build}/${springAppName}" />

    <!-- 日志格式 -->
    <property name="CONSOLE_LOG_PATTERN"
              value="%clr(%d{HH:mm:ss.SSS}){faint} %clr(${LOG_LEVEL_PATTERN:-%5p}) %clr(${PID:- }){magenta} %clr(---){faint} %clr([%15.15t]){faint} %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}}" />

    <!-- 控制台输出 -->
    <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>INFO</level>
        </filter>
        <!-- 日志输出编码 -->
        <encoder>
            <pattern>${CONSOLE_LOG_PATTERN}</pattern>
            <charset>utf8</charset>
        </encoder>
    </appender>


    <!-- Logstash -->
    <!-- 为logstash输出的JSON格式的Appender -->
    <appender name="logstash"
              class="net.logstash.logback.appender.LogstashTcpSocketAppender">
        <destination>127.0.0.1:5044</destination>
        <!-- 日志输出编码 -->
        <encoder
                class="net.logstash.logback.encoder.LoggingEventCompositeJsonEncoder">
            <providers>
                <timestamp>
                    <timeZone>UTC</timeZone>
                </timestamp>
                <pattern>
                    <pattern>
                        {
                        "severity": "%level",
                        "service": "${springAppName:-}",
                        "trace": "%X{X-B3-TraceId:-}",
                        "span": "%X{X-B3-SpanId:-}",
                        "exportable": "%X{X-Span-Export:-}",
                        "pid": "${PID:-}",
                        "thread": "%thread",
                        "class": "%logger{40}",
                        "rest": "%message"
                        }
                    </pattern>
                </pattern>
            </providers>
        </encoder>
    </appender>

    <!-- 日志输出级别 -->
    <root level="INFO">
        <appender-ref ref="console" />
        <appender-ref ref="logstash" />
    </root>

</configuration>

当两个项目都进行了简单配置，并进行微服务之间的调用之后，就可以在项目的控制台中看到spanID，这个是微服务跨服务调用的一个证明。此外也可以搭建一套elk来通过UI来查找日志，更加方便。后面会介绍ELK的搭建。